镜下特点：

          1．红髓内多个小结节形成；

2、结节内为杂乱排列的小血管样结构；

          3、硬化的背景，伴有炎细胞和含铁血黄素。

诊断：脾脏红髓硬化性结节性转化（Sclerosing nodular transformation of splenic red pulp），即所谓绳索样毛细血管瘤(so-called cord capillary hemangioma)。

 好病例，今天也读了一篇类似文章，挺新的，大家有兴趣可以看看

Clonal X-chromosome inactivation suggests that splenic cord capillary hemangioma is a
true neoplasm and not a subtype of splenic hamartoma
A Chiu1,*, M Czader2, L Cheng2, RP Hasserjian3, M Wang2, S Bhagavathi2,
EM Hyjek4, H Al-Ahmadie4, DM Knowles1 and A Orazi1
Splenic hamartoma is a rare tumor-like lesion composed of structurally disorganized red pulp elements. It has been hypothesized that two other splenic lesions, cord capillary hemangioma and myoid angioendothelioma, may fall within the spectrum of splenic hamartoma, simply representing morphological variants. In this study, we compared the vascular and stromal composition of cord capillary hemangioma and myoid angioendothelioma with those of classical hamartoma. In addition, we assessed the clonal vs polyclonal nature of the lesions in nine female cases by performing clonality analysis for X-chromosome inactivation at the human androgen receptor locus (HUMARA) on laser-assisted microdissected samples. In 15 of 17 cases, increased reticulin and/or collagen content was observed. The classical hamartoma cases showed a vasculature predominantly composed of CD8þ CD31þ CD34 splenic sinuses, whereas cases of cord capillary hemangioma and myoid angioendothelioma contained many CD8 CD31þ CD34þ cord capillaries, but very little CD8þ vasculature. All cases lacked expression of D2–40 and Epstein Barr virus-encoded RNA. All cases showed a proliferation index of r5% by Ki-67. Cases of classical hamartoma lacked significant perisinusoidal expression of collagen IV and low-affinity nerve growth factor receptor. Both markers were variably expressed in the other lesions.Increased CD163-positive histiocytes were found in four cases (three cord capillary hemangiomas and one myoid angioendothelioma). HUMARA analysis was informative in all nine tested cases, of which three cases
showed a non-random X-chromosome inactivation pattern, indicating clonality. All three clonal cases were cord capillary hemangiomas. Our study has shown that in spite of considerable morphologic heterogeneity and overlapping features, classical hamartoma and cord capillary hemangioma and myoid angioendothelioma are different in terms of their vascular and stromal composition. Clonality analysis supports a true neoplastic origin for the cord capillary hemangioma. A larger study using additional immunohistochemical and molecular studies is necessary to further evaluate the biological significance of the current findings.
Modern Pathology (2011) 24, 108–116; doi:10.1038/modpathol.2010.168; published online 17 September 2010
Keywords: clonality; cord capillary hemangioma; hamartoma; myoid angioendothelioma; sclerosing angiomatoid nodular transformation; spleen

学习

 翻了一下书，不知对否：

脾的多结节性血管瘤。

Sclerosing Angiomatoid Nodular Transformation (SANT): Report of 25 Cases of a Distinctive Benign Splenic Lesion.

American Journal of Surgical Pathology. 28(10):1268-1279, October 2004.
Martel, Maritza MD *; Cheuk, Wah MD +; Lombardi, Luciano MD *; Lifschitz-Mercer, Beatriz MD ++; Chan, John K. C MD +; Rosai, Juan MD *

Abstract:
Twenty-five cases of a morphologically distinctive vascular lesion of the spleen are described. The patients were 17 women and 8 men, ranging in age from 22 to 74 years (mean, 48.4 years; median, 56 years). The most common presentations were incidental finding of an asymptomatic splenic mass (13 patients), abdominal pain or discomfort (6 patients), and splenomegaly (4 patients). None of the patients had evidence of recurrent disease after splenectomy. The splenic lesion was solitary, measuring 3 to 17 cm, and sharply demarcated from the surrounding parenchyma. The cut surface revealed a mass of coalescing red-brown nodules embedded in a dense fibrous stroma. All cases showed a remarkably consistent multinodular appearance at low-power examination. The individual nodules had an angiomatoid appearance, in the sense that they were composed of slit-like, round or irregular-shaped vascular spaces lined by plump endothelial cells and interspersed by a population of spindly or ovoid cells. Some of the nodules (particularly the smaller ones) were surrounded by concentric rings of collagen fibers. Numerous red blood cells were present, as well as scattered inflammatory cells. Nuclear atypia was minimal, mitotic figures were extremely rare, and necrosis was consistently absent. The internodular stroma consisted of variably myxoid to dense fibrous tissue with scattered plump myofibroblasts, plasma cells, lymphocytes, and siderophages. Immunostaining revealed 3 distinct types of vessels in the angiomatoid nodules: CD34+/CD8-/CD31+ capillaries, CD34-/CD8+/CD31+ sinusoids, and CD34-/CD8-/CD31+ small veins, recapitulating the composition of the normal splenic red pulp. These features are therefore different from those of littoral cell angioma, conventional hemangioma, and hemangioendothelioma of the spleen. We interpret these angiomatoid nodules as altered red pulp tissue that had been entrapped by a nonneoplastic stromal proliferative process. The characteristic morphologic appearance, immunophenotype, and benign clinical course suggest that this is a distinctive nonneoplastic vascular lesion of the spleen that we propose to designate as sclerosing angiomatoid nodular transformation (SANT).

(C) 2004 Lippincott Williams & Wilkins, Inc.

American Journal of Surgical Pathology. 21(7):827-835, July 1997.
Arber, Daniel A. M.D.; Strickler, John G. M.D.; Chen, Yuan-Yuan B.S.; Weiss, Lawrence M. M.D.

Abstract:
Vascular tumors of the spleen include several different entities, some of which are unique to that organ. Twenty-two such proliferations were studied, including 10 hemangiomas, six littoral cell angiomas, four angiosarcomas, and two hamartomas. The hemangiomas included seven with localized tumors and three with diffuse angiomatosis of the spleen. All cases were studied by paraffin section immunohistochemistry with a large panel of antibodies. In addition, all cases were studied for the presence of the Kaposi's sarcoma-associated herpesvirus (KSHV) using the polymerase chain reaction. The morphologic findings were similar to those previously reported. All proliferations were vimentin positive, and one angiosarcoma was focally keratin positive. All cases reacted for CD31, whereas 20 of 22 were positive for von Willebrand's factor and 19 of 22 were positive for Ulex europeaus. CD34 expression in lining cells was identified in 10 of 10 hemangiomas, two of four angiosarcomas, and one of two hamartomas, whereas all six cases of littoral cell angioma were negative. CD68 was expressed in all cases of littoral cell angioma but was also positive in all three diffuse hemangiomas, two of seven localized hemangiomas, and two of four angiosarcomas. CD21 expression was restricted to the lining cells of littoral cell angioma, and CD8 expression was only identified in two of two hamartomas and two of four angiosarcomas. KSHV was not detected in any of the cases. These findings suggest that there are distinct immunophenotypic as well as morphologic features of splenic vascular tumors. Littoral cell angiomas have a characteristic CD34-/CD68+/CD21+/CD8- immunophenotype and hamartomas have a characteristic CD68-/CD21-/CD8+ phenotype. The frequent CD68 expression in diffuse hemangioma suggests an immunophenotypic difference from localized hemangioma of the spleen.

 从我老师那里得到的，上传共享。请注意知识产权问题哦。

3、讨论

脾脏的肿瘤中以淋巴瘤最为常见，其次则以血管肿瘤为多见，包括错构瘤、血管瘤、窦岸细胞瘤（衬细胞瘤）、血管内皮细胞瘤等。SANT是近来才确认的一种肿瘤，这一病变首先由Krishnan等于1993年提出并称之为索状毛细血管瘤（cord capillary hemangioma）或错构瘤的变型[3~4]，在Rosai和Ackerman第九版外科病理学中命名为多结节性血管瘤（multinodular hemangioma）[5]，强调其多结节特征性的组织学改变，Martel等[1]总结了意大利14例、香港9例及2例会诊病例共25例病变，并根据其组织学特征、免疫表型称之为“脾脏硬化性血管瘤样结节性转化”，并认为表明该病变由脾脏红髓成分组成，缺乏白髓成分，可以认为是一种错构瘤样病变，但特有的结节性血管瘤样改变和传统的错构瘤不同。

SANT的病理形态具有特征性，大体上常为单发肿块，境界清楚，圆形或分叶状。镜下为多结节性血管瘤样少数似肉芽肿样改变，每个结节周围有致密或较致密的胶原化纤维组织包绕。结节内聚积狭窄的、窦样血管腔，内衬肥胖的内皮细胞，免疫组化显示为既有CD34阳性表达的小血管及又有少量CD8阳性表达的窦性腔隙，部分内衬细胞CD68阳性，而CD21及CD35阴性，CD31表达细胞明显较多，形成极其复杂的网状结构。SMA阳性细胞成簇分布在血管腔隙之间，Ⅳ型胶原显示大量基底膜样物质沉着在复杂的血管网中。结节间间质梭形细胞局灶性Actin阳性，但Desmin、CD21、CD35和HHV8LNA-1阴性，Ki67染色显示细胞增殖指数<5%。

确切地讲SANT病变的本质尚不完全清楚，血管瘤样结节性转化是一个带有描述性的诊断名称，对该病变是一个新生性肿瘤，还是瘤样病变如错构瘤、血管瘤，甚至是否为血肿的最后转归仍有待于进一步阐明。

4、鉴别诊断

脾脏SANT组织学具有多结节性特征，确认以后容易识别，但在以前往往诊断为其他病变，本组有2例以前曾诊断为脾脏血管瘤广泛机化和错构瘤伴梗死机化结节形成，在病理诊断中SANT常须和以下病变鉴别。1）经典型脾脏错构瘤：是由脾脏红髓组织组成的瘤样病变，在免疫组化表型上和脾SANT相似，但SANT病灶境界清楚以及纤维组织增生形成多结节改变不同于经典脾脏错构瘤，故二者不难区别。2）脾血管瘤和淋巴管瘤：常常为单一组成模式的肿瘤，血管瘤常为海绵状血管瘤，少见为毛细血管瘤，组织学上和软组织及其它部位的血管瘤或淋巴管瘤相似由海绵样扩张不一的血管腔或毛细血管组成，免疫组化CD31、CD34阳性，但不表达CD8，虽然可发生梗死、纤维化和囊性变但不形成SANT特征性的血管瘤样结节；3）杆菌性血管瘤病：是一种非常少见的反应性瘤样血管增生，多见于免疫缺陷病人，亦可发生于脾脏，病变由小血管和毛细血管组成，排列成分叶状，血管内皮细胞肿胀似上皮样血管瘤，血管之间见颗粒状物质，Warthin-Starry染色可见杆菌类细菌，细菌周围有中性粒细胞浸润和细胞碎片，但不形成多结节性病变。4）脾衬细胞瘤（Littoral cell Tumor）：瘤组织主要由大小不一的窦样腔隙组成，腔内乳头形成，腔隙及乳头表面均衬内皮样细胞，免疫组化CD31、CD68、CD21阳性，而CD34阴性，并且没有多结节纤维化改变。5）脾血管内皮瘤：是一种中间型血管肿瘤，血管内皮细胞肿瘤样增生并间质黏液变及纤维组织增生，但增生内皮细胞常有轻及中度异型改变，免疫组化亦为CD31、CD34阳性，CD8阴性。6）以肉芽肿样改变的病变  脾SANT在低倍镜下类似肉芽肿结节，但各种肉芽肿病变有大量组织细胞、多核巨细胞，活动性肉芽肿可见坏死；结节病可见较多的巨细胞，结节周围炎症细胞浸润而无明显血管增生。7）脾炎性假瘤：可为边界清楚的灰白色肿块，但镜下为增生的肌纤维母细胞及各种炎症细胞浸润包括浆细胞、淋巴细胞及中性白细胞以及多量组织细胞增生形成结节，免疫组化SMA、CD68表达明显，缺乏血管内皮细胞标记。8）其他结节样病变，少见的脾脏转移癌肿周围可有纤维组织增生形成结节样病变，但转移癌细胞异型明显。

Sclerosing Angiomatoid Nodular Transformation (SANT): Report of 25 Cases of a Distinctive Benign Splenic Lesion.

American Journal of Surgical Pathology. 28(10):1268-1279, October 2004.
Martel, Maritza MD *; Cheuk, Wah MD +; Lombardi, Luciano MD *; et al.